Founder's Day, Founders Day, or Founders' Day and variations may refer to:
- Founder's Day (Rome), better known as the Parilia, a festival in ancient Rome eventually taken to honor the city's founding
- Founders' Day (Ghana), a public holiday in Ghana
- Founder's Day (Music Festival) an annual campus festival at Vassar College
- Founders' Day (Scouting), a Scouting commemoration associated with Scouts' Day
- Founders Day (South Africa), an observance and former public holiday in South Africa
- "Founder's Day" (The Vampire Diaries), a 2010 episode of the TV series The Vampire Diaries
- Founders Day, a 2023 American slasher film directed by Erik Bloomquist.
- Founders' Day, a former public holiday in Rhodesia
- Founder's Day, a holiday of the American Revolution
- Founder's Day, an annual event at many Indian private boarding schools, such as The Doon School
If an internal link led you here, you may wish to change the link to point directly to the intended article. Category: